Safety lock for scraper apron

ABSTRACT

A safety lock is mounted on the apron of a wheel tractor or tractor drawn scraper for selectively holding the apron in a raised position. The safety lock comprises a pin member slidably mounted on the apron and normally retained in a retracted position during scraper operation. The apron may be raised and the member extended over a sidewall of the scraper bowl to positively maintain the apron in such raised position.

Unite States Patent Flint et al. [4 1 Jan. 18, 1972 [541 SAFETY LOCK FOR SCRAPER APRON 2,216,235 10/1940 French ..37/l26 [72] Inventors: Walker H. Flint, Peoria; Charles J. Chap- 3:2 2,665,153 1/1954 Teichmann 292/144 [73] Assignee; Caterpillar Tractor Co, Peoria []l 3,274,71 1 9/1966 Johnson BI 31 "37/129 2,804,702 9/1957 Corser et a1 ..37/l26 AC [22] 1969 2,332,628 10/1943 French ..37/l26 AC [21] App]. No.: 859,378

Primary Examiner-Robert E. Pulfrey Assistant Examiner-R. T. Rader [52] US. Cl ..37/l26, 37/129, 37/134 An rney Fryer, Tjensvold, Feix, Phillips & Lempio [51] Int. Cl. ..E02f 9/24 [58] Field of Search ..292/l50, 151, 144, 145; [57] ABSTRACT 37/134 129 A safety lock is mounted on the apron of a wheel tractor or 56] References Cited tractor dranm scraper for selectively holding theapron in a raised position. The safety lock comprises a pin member UNITED STATES PATENTS slidably mounted on the apron and normally retained in a retracted position during scraper operation. The apron may be 305,294 9/1884 Corn ..292/15O raised and the member extended Over a sidewall f h Scraper 6772046 6/1901 l bowl to positively maintain the apron in such raised position. 1,508,029 9/1924 Sega] ..292/15O 1,920,868 8/1933 Kirk ..292/144 9 Claims, 6 Drawing Figures PATENTEDJAIHBWZ 3,634,955

SHEET 1 BF 4 I'NVENTORS WALKER H. FLINT CHARLES J. CHAPPELL BY 7 I ATTORNEYS PATENTEU M18 872 SHEET 2 0F 4 INVENTORS WALKER H. FLINT CHARLES J. CHAPPELL.

a o I aw WW ATTORNEYS B) I J SHEET 3 BF 4 PATENTEB M18872 KINVENTORS WALKER H. FLINT CHARLES J. CHAPPELL ATTOZTEYS BY W W PATENTEI] JAII 1 a ma SHEET 0F 4 INVENTORS WALKER H FLINT CHARLES J. CHAPPELL BY J 0 f? 1% #4 4 W W I 276% ATTORNEYS SAFETY LOCK FOR SCRAPER APRON Continuous efforts on the part of the earth-moving industry to make their products highly safe has dictated the need for an efficient safety lock for positively retaining the apron of a wheel tractor or tractor-drawn scraper in a raised position during servicing. The common practice is to insert wooden blocks or the like between the sidewalls of the scraper bowl and the aprons sideplates to maintain the apron in such raised position. Inadvertent dislodgement or shearing of the blocks could result in injury to men working thereunder.

An object of this invention is to provide an economical and efficient locking means for positively retaining a scrapers apron in a raised position. Such locking means is movably mounted on the apron to be normally retracted substantially within the confines of the apron. When the apron is raised for servicing or the like, the locking means is extended outwardly from the apron and into overlying relationship with respect to the top edge of a sidewall of the scraper bowl.

Other objects of this invention will be apparent from the following description and accompanying drawings wherein:

FIG. I is a side elevational view of a wheel tractor scraper employing a locking means embodiment of this invention therein;

FIG. 2 is an enlarged cross-sectional view taken in the direction of arrows 2-2 in FIG. 1, but showing an apron in its raised position.

FIG. 3 is an enlarged plan view taken in the direction of arrows 33 in FIG. 2;

FIG. 4 is a partially sectioned, front elevational view of a modified locking means;

FIG. 5 is an enlarged, partially sectioned view of the FIG. 4 locking means; and

FIG. 6 is a view taken in the direction of arrows 6-6 in FIG. 5.

The wheel tractor scraper illustrated in FIG. ,1 comprises a two-wheel tractor l0 operatively connected to a scraper 11 by spaced draft arms 12 and attendant conventional structures. The scraper comprises a bowl 13 normally closed at its front end by an apron 14 pivotally mounted thereon by pivot pins 15. The apron is adapted to be raised and pivoted counterclockwise about the pivot pins by means of a rod 16 operatively connected by standard linkages to an actuating cylinder rod 17.

Referring to FIGS. 2 and 3, this invention is primarily directed to a safety lock or locking means 18 movably mounted on the apron to be normally retracted substantially within the confines thereof, as illustrated by the rightwardly disposed locking means in FIG. 2. When the apron is raised, the locking means is adapted to be selectively moved or extended outwardly and into overlying relationship with respect to a sidewall of the scraper bowl as illustrated by the leftwardly disposed locking means. Although two such locking means are illustrated, tests have shown that one such locking means is normally adequate for positive maintenance of the apron in its raised position.

Each locking means (FIG. 3) comprises a bolt or pin member 19 slidably mounted in a bifurcated bracket 20 welded or otherwise suitably secured to the apron. A tube or collar 21 is secured between the bracket members and has an eyebolt 22 attached thereto. One end of the flexible chain 23 is attached to the eyebolt whereas the other end thereof is suitably attached to the eyelet end of a cotter pin 24, which cooperates with the bracket to provide positioning means for the pin member.

The cotter pin is removably mounted in an aperture 25 formed through pin member 19. The cotter pin facilitates selective positioning thereof between its retracted and extended positions illustrated in FIG. 2. The positioning means may further comprise a setscrew 26 threadably attached to the pin member to prevent shifting thereof beyond the sidewall of the scraper bowl and the bracket members.

In normal operation pin member 19 will be retained in its retracted position by positioning the cotter pin on the inboard side of the bracket members. When it is desired to replace scraper blade 27, for example, the apron is raised relative to thebowl and the cotter pin is removed from its retaining aperture. The pin member is then extended (FIG. 3) into overlying relationship with the adjacent sidewall of the bowl.

The cotter pin is reinserted into aperture 25, on the outboard side of the bracket members which thus cooperate therewith to comprise the positioning means. Setscrew 26 cooperates with the cotter pin to positively retain the pin member in such extended position. The actuating lever (not shown) operatively associated with rod 16 is then moved in the operators cab to lower the apron so that the pin engages the top edge of the bowls sidewall to positively retain the apron in a set, raised position. The structural integrity of the pin members and interrelated structures is preferably sufficient to withstand the full closing force of the apron.

It should be understood that pneumatically or hydraulically actuated power 'or control means may be operatively associated with the pin members, if so desired, to selectively actuate the pins from a remote location, such as the operator's station. Such power means may comprise a suitably arranged hydraulic cylinder either connected directly or through suitable linkage means to the pin member. For example, as illustrated in FIG. 2 a double-acting hydraulic cylinder 28 may have its casing secured to the apron.

The cylinders rod may be mechanically connected to the pin member to selectively reciprocate same. The actuating handle for a manually actuated control valve 29 may be positioned in the operators station if so desired. The valve is operatively connected to the double-acting cylinder in a conventional manner to selectively communicate a pressurized fluid source (not shown) thereto to reciprocate the pin member. Normally, such an automatic control system would not require the cotter pin.

A modified locking means 18a, illustrated in FIGS. 4-6, includes numerals identical to those appearing in FIGS. 1-3 to depict corresponding structures with the former numerals each being accompanied by an a. The modified locking means comprises a bolt or pin member 19a slidably mounted in a bushing 21a welded to spaced brackets 20a which are suitably secured to an apron 14a. An upstanding lug 260 may be secured to the apron to form part of a positioning means limiting the extent of inboard movement of the pin member relative to the apron.

A key-type retainer or retaining means 24a is removably attached to the bracket, secured to the sidewall of the apron, by means of a bolt 30. Such retainer may thus be selectively inserted and connected into a slot 31 and 32 formed in the pin member to provide a positioning means therefor. A rectangular aperture 33 is formed through the sidewall of the apron to permit selective extension of pin member to its FIG. 4 position, whereat it overlies sidewall 13a of the scraper bowl.

Loosening and removal of bolt 30 will permit the retainer to be removed from slot 31 and repositioned in slot 32. The matching, juxtaposed straight edge portions formed in the slots and on the end of the retainer prevent accidental dislodgement of the retainer. If so desired, the slots may comprise an arcuate configuration (not shown) conforming to an arcuate end portion formed on the retainer. Such a further modification would enable the retainer to remain attached to the apron when it is loosened and pivoted mom of the two locked positions.

A screwdriver or like device can be inserted into one of the slots for manually repositioning the pin member in collar 210. Should the pin become stuck due to the collection of rust, dirt or the like between it and the collar, a capscrew 34, threadably attached to the end of the pin member, may be rotated to free same. It should be noted that a channel 35 is preferably secured to the apron to house the locking means therein.

We claim:

1. In an earthmoving scraper comprising a bowl defined in part by upstanding sidewalls and an apron attached to and movably mounted in said bowl, the invention comprising at least one locking means comprised of a member movably mounted on said apron to be normally retracted substantially within the confines of said apron and to be selectively moved out of the confines of said apron and extended into an engaging and holding relationship with respect to at least one of the sidewalls of said bowl when said apron is raised in said bowl, and means operatively associated with said member for selectively holding said member in its retracted or extended position on said apron.

2. The invention of claim 1 wherein two of said locking means are movably mounted on said apron with each of said locking means positioned thereon to be extended into overlying relationship with respect to a respective one of two opposed sidewalls of said bowl.

3. The invention of claim 1 wherein said positioning means comprises a bracket secured to said apron and having said member slidably mounted thereon and a pin removably attached to said member to be positioned on an inboard or an outboard side of said bracket whereby said locking means may be selectively held in its retracted or extended position, respectively.

4. The invention of claim 3 wherein said positioning means further comprises means attached to said member between a sidewall of said apron and said bracket, limiting the extended movement of said member.

5. The invention of claim I wherein said positioning means comprises a retaining means attached to said apron for selective connection to said member to maintain it in its retracted or extended position.

6. The invention of claim 5 comprising means forming spaced slots in said member, said retaining means comprising a key-type retainer adapted to be selectively positioned in one of said slots.

7. The invention of claim 5 wherein said positioning means further comprises a lug secured to said apron and positioned thereon to limit the extent of inboard movement of said member relative to said apron.

8. The invention of claim 1 further comprising control means operatively associated with said locking means for selectively moving said locking means between its retracted and extended positions from a remote location on said scraper.

9. The invention of claim 8 wherein said control means comprises a cylinder having a reciprocal actuating rod thereof operatively connected to said locking means. 

1. In an earthmoving scraper comprising a bowl defined in part by upstanding sidewalls and an apron attached to and movably mounted in said bowl, the invention comprising at least one locking means comprised of a member movably mounted on said apron to be normally retracted substantially within the confines of said apron and to be selectively moved out of the confines of said apron and extended into an engaging and holding relationship with respect to at least one of the sidewalls of said bowl when said apron is raised in said bowl, and means operatively associated with said member for selectively holding said member in its retracted or extended position on said apron.
 2. The invention of claim 1 wherein two of said locking means are movably mounted on said apron with each of said locking means positioned thereon to be extended into overlying relationship with respect to a respective one of two opposed sidewalls of said bowl.
 3. The invention of claim 1 wherein said positioning means comprises a bracket secured to said apron and having said member slidably mounted thereon and a pin removably attached to said member to be positioned on an inboard or an outboard side of said bracket whereby said locking means may be selectively held in its retracted or extended position, respectively.
 4. The invention of claim 3 wherein said positioning means further comprises means attached to said member between a sidewall of said apron and said bracket, limiting the extended movement of said member.
 5. The invention of claim 1 wherein said positioning means comprises a retaining means attached to said apron for selective connection to said member to maintain it in its retracted or extended position.
 6. The invention of claim 5 comprising means forming spaced slots in said member, said retaining means comprising a key-type retainer adapted to be selectively positioned in one of said slots.
 7. The invention of claim 5 wherein said positioning means further comprises a lug secured to said apron and positioned thereon to limit the extent of inboard movement of said member relative to said apron.
 8. The invention of claim 1 further comprising control means operatively associated with said locking means for selectively moving said locking means between its retracted and extended positions from a remote location on said scraper.
 9. The invention of claim 8 wherein said control means comprises a cylinder having a reciprocal actuating rod thereof operatively connected to said locking means. 